For some reason, the first evade bug moment I remember happened in Zul'Farrak. We were clearing the basilisk pulls before attempting Antu'sul (why is it that the optional bosses always have a couple of sweet warrior drops?) and the mage in the group wanted to skip the whole thing. Impatient, he decided to start nuking away from atop one of the hills surrounding the area and managed to pull aggro, but the basilisk couldn't path up to him (and to be honest I'm not sure how he got up there) and promptly went evade. He wouldn't come down because he rightly knew the mob would hit him, and so it took us a solid ten minutes of arguing before he finally came into the monster's reach so that I could taunt it.
I'm thinking about this because of the Isle of Quel'Danas dailies, specifically the quest Crush the Dawnblade. For some reason whenever I do this quest I run into Dawnblade Summoners who are evading. This puzzles me because I can't understand why a ranged mob is evading: it doesn't have to path to anything to hit it, just get into range. Is there some way a hunter or some other ranged class can shoot them but stay out of their range?